Rotary fan.



T. J. STURTEVANT.

ROTARY FAN.

APPLICATION FILED IEB.19,1913.

1,087,995. Patentad Feb. 24, 1914 2 in 'LlBTS-SHEBT Z.

WITNESSES. r INVENTOR:

UNITE STATES PATENT OFFICE.

.mems JDSEPH @UBTEVANT, OF WELLESLEY, MASSACHUSETTS, ASSIGNOB TO STURTEVANT MILL GOMPAN Y, A CORPORATION OF MAINE.

ROTARY FAN.

Patented Feb. 24, 1914. Serial No. 749.387.

I0 661 whom it may concern Be it known that I THOMAS Josnrn S'rUR'rEvANT, a citizen of the United states, residing at Wellesley, in the county of Norfolk and State of Massachusetts, have mve ed or discovered certain new and use 'ful Improvements in Rotary Fans, of which the following is a specification, reference being had therein to the accompanying drawi his invention relates to air agitating devices or fans, and has for its object to provide a fanevhich will produce reversing or pulsating air currents which may be utilized for any desired purpose. To this end the improved air agitating device or fan is provided with reversely inclined Wings or blades which are preferably arranged alternately, thatis to sa alternateblades inclined inv different directions, although these reversely inclined blades maybe arranged in alternate groups, if desired; or if it be desired to make the air currents stronger in one direction than the other a greater number of blades may be inclined One way than the other, as by providing a single blade inclined in one direction, between pairs of blades inclined in the opposite direction.

is an elevation of a drum type of fan embodying the present invention, and Fig.'2 1s a section thereof on line 2---2, Fig. 1. Fig. 3 is a face view of a propeller type of fan embodying the invention, and Fig. 4 is a sectional side view of the same, the section being taken on-line 4, Fig. 3.

Referring to Figs. 1 and 2 of the drawings the drum type of fan therein illustrated comprises closed upper and lower ends formed by disk-like heads .12, a central stiffening or bracing ring 13 and alternately inclined wings or blades 14 suitably secured, as by rivets 15, to the said endiheads and ring. The central ring 13 is preferably employed in the drum type' of fan proportioncd as shown in the drawings, for the purpose of stiffening or bracing the wings or blades 14; although, as will be understood,'.with a narrower or thinner drum type of fan this central bracing or stit'l'em ing ring may not be necessary. In the construction shown the end heads 12 are reinforced or braced by plates or cohhirs 16 attached thereto and through the medium In the accompanying drawings Figure 1 of one or more of which the drum is attached to the vertical rotating shaft 12.

In-the form of the invention shown in Figs. 3 and 4 the hub 18 of the propeller fan is provided with projections 19 to which alternate, reversely inclined fan blades 20 and 21 are attached, the blades clined in one direction relative to the axis of the rotating shaft 22 carrying the fan, while the blades 21 are inclined in an opposite direction relative to said axis.

In the operation of either type of fan hereinbefore described the rotation of the fan will agitate the air in pulsatin or reversing currents which may be utilized for any desired purpose, as, for example, for vibrating the screens of separating machines employed for screening very finely pulverized materials. Such vibrations of the screens by pulsating or reversing air currents obviates the necessity of jarring mechanism such as has sometimes been heretofore employed in separating machines, and thus avoids such wear or injury to finemesh wire-cloth screens as might result from the harsher action of jarring mechamsm,

Having thus described my invention I claim and desire to secure by Letters Patent:

1. A rotary fan comprising independent, separated wlngs or blades which are reversely inclined relative to their plane of rotation, thus being adapted to cause reversing or'pulsating air currents when in operation.

2. A rotary fan comprising alternate, independent, separated wings or blades which are reversely inclined relative to thei plane of rotation, thus being adapted to cause reversing'or pulsating air currents when in operation.

3. A drum type of rotary fan comprising independent, s parated wings or blades which are reverscly inclined relative to their plane of rotation, thus being adapted to cause reversing or pulsating air currents when in operation.

4. A drum type of rotary fan comprising alternate, independent, separated wlngs or blades which are reversely inclined relative to theirplane of rotation, thus being adapted to cause reversing or pulsating air currents when in operation.

20 being in 5. A drum type of rotary fan consistingfi of closed end heads and reversely inclined d wings or blades between said heads and adapted to cause reversing or pulsating air currents when in operation.

6. A drum type of rotary fan consisting of closed end heads and alternate reversely inclined wings or blades between said heads and adapted to cause reversing or pulsating air currents when in operation.

7. A drum type of rotary fan consisting of closed end heads, reversely inclined wings or blades between said heads and adapted to cause reversing or pulsating air currents when in operation, and a central stiffening or bracing ring to which and also to said heads said wings or blades are attached.

8. A drum type of rotary fan consisting of closed end heads; alternate. reversely in- (-lined wings or blades and adapted to cause reversing or pulsating air currents when in operation, and a central stiffening or bracing ring to which and also to said heads said wings or blades are attached.

9. A drum type of rotary fan consisting of closed end heads, reversely inclined wings or blades between said heads and adapted to cause reversing or pulsating air currents between said heads 1 i i i 1 l l l I i i when in operation, and a vertical shaft by Whicli said fan is carried.

10. A drurn type of rotary fan consisting of closed end heads, alternate, reversely inclined wings or blades between said heads and adapted to cause reversing orpn'lsating air currents when in operation, and a vertical shaft by which said fan is carried.

1]. A cylindrical type of rotary fan comrising separated wings or blades which are rererscly inclined relative to their plane of rotation, being thus adapted to generate rew-rsing or PlllSll.tlli-" currents when the fan is in rotation.

l2. cylindrical type of rotary fan comprising separated wings or blades Which are alternately reversely inclined relative to their plane of rotation, being thus adapted to generate reversing or pulsating currents when the fan is in rotation.

In testimony whereof 1 affix my signature, in presence of two witnesses.

THOMAS JOSEPH STURTEVANT.

W'itnesses WM. T. DOYLE, H. A. Tommnson. 

